package test;

import java.util.Scanner;

public class test1 {
    public static void main(String[] args) {

            Scanner scanner = new Scanner(System.in);
            String str = scanner.next();

            //write your code here......
            StringBuilder newstr= new StringBuilder(str);
            for(int i=newstr.length()-3;i>=0;i-=3){
                newstr.insert(i,",");
            }
            System.out.println(newstr.toString());

        }
}
